Low Stretched Premixed Methane-Air Flame.

Abstract

A numerical study of low stretched premixed methane-air flame in a counterflow configuration is conducted. The present simulation includes detailed transport properties and chemical kinetics. It is found that near the flammability limit, there is a radiation extinction branch in addition to the normal stretch extinction branch, which has been extensively studied at a large stretch rate. Furthermore, far from the flammability limit, it is found that there are two stable flames, a normal flame and a weak flame which are the results of interaction between the stretch effect and the radiation effect, at a certain extent of stretch rate. In addition, the present results show that the flammability limit obtained in counterflow configuration cannot be extended directly to the flammability limit of its corresponding one-dimensional free propagating premixed flame.